This invention generally relates to medicine dispensing devices, and more particularly, relates to devices for delivery of medication to patients who are unable to swallow or accept medication orally.
For patients who have impaired ability to swallow, medications have been administered through a tube passing from the patient's nasal cavity and pharynx into the stomach, referred to as the naso-gastric route or through the mouth. For example, U.S. Pat. No. 4,205,676 describes apparatus employing pumped air to force fluids, such as a liquified food product, into the stomach by way of a naso-gastric tube. Although this patent describes replenishment of "flowable" material supply within containers from which the material is forced by air pressure, it does not provide for administering solid tablets or capsules to patients unable to swallow.
In order to dissolve solid or powdered medications, U.S. Pat. Nos. 708,224, 2,798,488, and 4,306,554 describe syringe units which include separate compartments for the solid and solvent. The compartments are interconnectable so as to enable dissolution of the solid and displacement of the solution. U.S. Pat. No. 3,351,058 describes a two compartment syringe unit for placement of solid within one compartment separated by a frangible membrane in the second compartment having flexible walls for holding a liquid ingredient. In use, sufficient mechanical pressure is applied to the flexible walls of the fluid compartment so that the frangible membrane will be ruptured by internal hydraulic pressure, thereby enabling flow of the liquid ingredient into the compartment holding the solid ingredient to form a solution.
When the prescribed medication is in the form of a pill or tablet, the devices described in these patents require sufficient period of time for complete dissolving of the tablet in solution. While prior pulverization of the tablet, for example with mortar and pestle, can be employed in order to insert a powdered solid into the device described in these patents, the prior pulverization process introduces problems of contamination and inaccuracy in the level of the dosage as well as the inconvenience of additional material transfer.